Tensile strength of large-scale incipient rock joints: a laboratory investigation

Shang, J. , West, L.J., Hencher, S.R. and Zhao, Z. (2018) Tensile strength of large-scale incipient rock joints: a laboratory investigation. Acta Geotechnica, 13(4), pp. 869-886. (doi: 10.1007/s11440-017-0620-7)

Abstract

In this paper, a testing methodology was developed in the laboratory to measure the tensile strength of large-scale incipient rock joints. In the test, an expansive grout was used to develop the tensile force. Each test comprises two phases: Phase i test and Phase ii test. The Phase i test identified sample failure time, while the Phase ii test measured the corresponding tensile force arising from the expansive grout. Ostensibly homogeneous rock samples without incipient joints were firstly tested to establish the methodology. Tensile strength of block samples containing incipient rock joints was then measured using the established testing scheme. The test results have been compared with those obtained from conventional Brazilian and uniaxial tension tests as suggested by ISRM. The proposed approach is capable of giving a measure of tensile strength of large-scale incipient rock joints, although somewhat smaller strength than that from the standard approaches was occasionally measured in the preliminary tests on ostensibly homogeneous samples. Effects of stress concentration, sample scale, loading rate and expansive tensile force on the testing results were discussed. Furthermore, this simple and practical testing scheme is proposed for the measurement of the in situ tensile strength of rock and incipient discontinuities in the field, which if successful will provide a more scientific guidance on the rock mass classification and engineering design.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Shang, Dr Junlong
• Authors: Shang, J., West, L.J., Hencher, S.R., and Zhao, Z.
• College/School: College of Science and Engineering > School of Engineering > Infrastructure and Environment
• Journal Name: Acta Geotechnica
• Publisher: Springer
• ISSN: 1861-1125
• ISSN (Online): 1861-1133
• Published Online: 18 December 2017
• Copyright Holders: Copyright © 2017 The Authors
• First Published: First published in Acta Geotechnica 13(4): 869-886
• Publisher Policy: Reproduced under a Creative Commons License